Chromis Question
- Thread starter Tat2demon
- Start date
AquaticFins
Premium Member
Unless the tank is quite large, it is indeed likely that the larger chromis will eventually kill off the smaller.
Chromis have fairly large territories compared to the size of the average aquarium...as such, they will usually whittle their number down to fit the available space as they mature.
I've found the smaller chromis species (such as Chromis viridis) to generally control a 3-6 square foot territory per pair, depending on the density of rockwork and aquascaping design. Larger chromis (Chromis cyaneus, for example) require much more space.
In short, you'll almost certainly need an aquarium of several hundred gallons to support that many chromis long-term.
They really don't school as adults in anything but the very largest of aquariums. Instead, they will pair off...and like any other damselfish, at that point it just comes down to how many territories the aquarium has space for. If that number is less than the number of fish, the chromis will reduce the number of fish until the remainder can coexist happily.
Hope that helps!
EDIT: Oh, and the rough estimate of territory size I suggested earlier really doesn't take breeding in to account. Once a pair spawns, they often will consider their territory effectively doubled until their eggs hatch. In even a fairly large home aquarium (a 6'x2' 180G, for example), a breeding pair of chromis may consider half or more of the aquarium "theirs" and do their best to keep all the other fish penned up on one side of the tank. If there isn't sufficient space for the other residents of the tank, it's easy for that to result in fish deaths.
Chromis have fairly large territories compared to the size of the average aquarium...as such, they will usually whittle their number down to fit the available space as they mature.
I've found the smaller chromis species (such as Chromis viridis) to generally control a 3-6 square foot territory per pair, depending on the density of rockwork and aquascaping design. Larger chromis (Chromis cyaneus, for example) require much more space.
In short, you'll almost certainly need an aquarium of several hundred gallons to support that many chromis long-term.
They really don't school as adults in anything but the very largest of aquariums. Instead, they will pair off...and like any other damselfish, at that point it just comes down to how many territories the aquarium has space for. If that number is less than the number of fish, the chromis will reduce the number of fish until the remainder can coexist happily.
Hope that helps!
EDIT: Oh, and the rough estimate of territory size I suggested earlier really doesn't take breeding in to account. Once a pair spawns, they often will consider their territory effectively doubled until their eggs hatch. In even a fairly large home aquarium (a 6'x2' 180G, for example), a breeding pair of chromis may consider half or more of the aquarium "theirs" and do their best to keep all the other fish penned up on one side of the tank. If there isn't sufficient space for the other residents of the tank, it's easy for that to result in fish deaths.
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